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Geoff Lister

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Everything posted by Geoff Lister

  1. I have the Celestron Plossl eyepiece set, and find that the 6mm & 8mm have very limited eye relief; almost useless for me, as I wear glasses, and without glasses my eyelashes touch the surround for the final lens. For the higher magnifications, I tend to use the 13mm or 17mm with a x2 Barlow, or the Svbony Ultrawide 9mm & 6mm. Geoff
  2. I have 3 similar, and yet very different, mounts, with the same tripod. The Skymax has the Synscan GoTo handset; the Skyprodigy uses its built-in webcam to plate-solve for alignment, and a different wired handset and software interface; and the Cosmos uses a WiFi link to my tablet. Whilst looking through an eyepiece, I find it much easier to use a handset with proper, tactile, buttons; than trying to press "virtual" buttons, somewhere towards the edge of my tablet's screen. Each of the above mounts are supplied with an 8-cell battery holder, that sits in a little satchel, and plugs into the external supply socket. These are designed for use with 1.5V alkaline cells, and the mount's electronics needs close-to 12V for reliable operation. If any of the 16 spring or pad contacts are not pristine, the increased resistance can cause the voltage to drop, particularly when the mount is slewing at maximum rate. I tend to use a 12V, 2A, plug-top PSU; and for a portable supply, a pair of 6V, 2600mAh battery packs, borrowed from my radio-controlled model sailing yachts, and a "Y" lead to get 12 to 14V. These sit neatly in the satchel, and I have added stick-on plastic hooks to the mounts, to hold the satchel. Geoff
  3. I went for a pair of the budget 7-21mm zoom eyepieces for my binoviewer. They are a good starting point. The slightly more expensive 8-24mm is better, but I only have one. However, I think it unlikely that most astronomers could justify a pair of the superb Baader Hyperion Mk IV 8-24mm zooms - I had to think hard before I pressed the "Buy" button for one. A pair of 32mm Plossls works for me. I am a glasses wearer, and the excellent eye relief is worth having. They are equivalent to 16mm with a X2 Barlow. As I have several Synta systems, I also use a pair of the "standard" 25mm eyepieces, with and without Barlow (Barlow is needed for focus on the Skyliner's Dobsonian Newtonian OTA). Geoff
  4. Yes. The brain expects a similar image in both eyes. It is unnatural to close one eye. When you are looking at fine detail on Jupiter, Saturn or the Moon, binoviewers seem to help the brain to process the detail. I have found that, with advancing age, and particularly with bright objects, I have "floaters" in my eyes. By having the same image in both eyes, the brain seems to blend the image, and the floaters almost disappear. Geoff
  5. Hello Craig, and welcome to SGL. Several of those above have suggested the book "Turn Left at Orion". As a taster, there is a limited coverage of this book on the web site https://www.cambridge.org/turnleft Geoff
  6. I use Brightest Star alignment, but found that, far too often, the suggested second alignment star was behind a tree, fence or house. So, I spent some time with "Stellarium", adjusting date and time, for dusk at the middle of each month of the year, and from a table of 14 of the brightest stars visible from my observing position, selected several with compass direction and altitude, so that I could get good azimuth and altitude separation for a good alignment, and avoiding those close to the zenith or horizon. It has saved me a lot of frustration, and I can align before it gets really dark, go in for tea, and come back to excellent GoTo and tracking. At the moment, Mars is a good first, manual target, and then I can select 2 of my tabulated stars for the automatic slew. This is my table, including "idiot's" guide as to the relative positions, and a similar table for an hour before dawn. My house obscures the NW to NE arc, but with a gap for Polaris (not the brightest of stars, but a backup second star if there is partial cloud cover). This is for my Az/Alt Skymax & Skyliner (and Virtuoso - using the Skyliner's handset) mounts; I am not sure if it would be the same set for an EQ mount. Geoff
  7. This was a photo that I took a while ago, showing a range of optical tubes and their associated mounts. They all have the "standard" Vixen/Skywatcher/Celestron/... dovetail bar, and any one of these OTAs will fit any one of these mounts, although some of the longer OTA/smaller mount combinations have altitude limitations. However, some mounts have similar mechanical interfaces, the AZ4 mount is similar, but with manual controls to adjust azimuth and elevation. The Skyprodigy mount has a plastic cowl round the dovetail clamp, to give a snug fit with the 70 mm refractor OTA, and I had to trim it back to fit my 127 Mak. In colour, although those of Saturn are delicate shade variations of light cream. Unfortunately Jupiter and Saturn are now very low targets at dusk, and, at 52 degrees N, you will have to wait until about early May before the Sun moves out of the way, and they become visible at dawn, just before the Sun rises, and August for a better evening view. You will be looking at low altitude through the Earth's atmosphere, so visibility will be very variable. With my 127mm Mak., I have seen the blue/green colours of Uranus and Neptune. It was a challenge, first to find them amongst the background stars, and then, after using different size eyepieces, to optimise magnification V clarity, and then look for a long time until the atmospheric conditions gave me enough photons for my eye to see in colour - worth the effort. Geoff
  8. +1 for the Skywatcher 127mm Mak. I have 2, on Skymax Az/Alt mounts, and with the Synscan GoTo handset; 1 at home in the UK, and the other, currently, at a friends house, in France. Portability:- The total weight, with a few eyepieces and a couple of sets of batteries is about 11kg. This is how I used my other one:- The eyepiece has been replaced by a modified 640x480 Philips webcam, and I was able to get some decent videos of Jupiter & Saturn. The red wine is optional, but I found that it improved the pleasure of an evenings observing. This setup is also good for looking at the sun; with a solar filter cap on the front of the tube, and a smaller one on the finder 'scope. Geoff
  9. Yes. A good set of eyepieces will last you a lifetime, and beyond. When the astronomy bug bites, and it will, these can be used with your next optical tube, and the one after that - see my signature, I'm hooked. A 32mm Plossl will give you the most cost-effective wide-field view with a Mak-Cass optical tube. It's a good starting point to centre on an object. After that, there are many choices to increase the magnification; unfortunately, the best ones are expensive. Have a look at some of the pinned posts on this site to get further guidance. Geoff
  10. Yes, both for night-time and solar (with solar film cap).
  11. I replaced mine with a RACI equivalent - much more user-friendly. Geoff
  12. Provided that you mount the alternative OTAs with them balanced in the dovetail clamp, they should not place undue strain on the lcm 114 mount. I balance my OTAs, with a typical eyepiece in place, by sitting the dovetail bar at 90 degrees across a broom handle/piece of plastic pipe, and slide the OTA back and forth until it rests level on the handle/pipe. I mark the contact point with tippex, and when dry, a layer of varnish. This ensures minimum strain on the altitude motor-gearbox assembly. The photo, below, shows my 127mm Mak with the balance points for (a) a normal eyepiece, (b) binoviewer with 2 eyepieces, and (c) with my D3200 DSLR. Geoff
  13. Hello orca, and welcome to SGL. My first telescope, bought in 1986 to view Halley's Comet, was a Tasco 3T, very similar to your setup. It is an azimuth/altitude mount with a fork-and-rod coupling between the optical tube and tripod. The eyepieces have a diameter of 0.956" where they fit into the focuser draw tube, although I understand that your version has an adaptor, and will take the, more standard, 1.25" eyepieces. The mount is not very easy to use, but I got some fine views of the comet. If the manual supplied with your 'scope is difficult to understand, it may be useful to google "Tasco 3t" and look at some of the suggested sites - the USA "Cloudy Nights" astronomy forum, equivalent to this site, has some useful posts. This may help:- Tasco Luminova40-076420Inst.pdf I have made a dovetail rail & ring cradle, so that the optical tube can be used with my more-capable mounts:- Geoff
  14. With my 127mm Mak., I tend to start my sessions with my 32mm Plossl eyepiece. I have also replaced the 6x30 straight-through finder with its RACI equivalent - much easier to align to objects at higher altitudes. Geoff
  15. My Skymax and Skyliner mounts have the V3 Synscan handsets, and seem to be very sensitive to voltage dropping below about +11V. I have found that the battery packs for 8-off 1.5V AA size alkaline cells can suffer from poor contact at any of the 16 contact points. The voltage may hold up during initial startup, but can drop as soon as the mount does its first slew. As Martin mentioned above, when observing from my garden, I tend to use the 12V 1.5A or 2A mains plug-top supplies; some borrowed from the older standard external USB hard disks, or sold for use with the LED flexible stick-on light strips. Geoff
  16. This is a selection of power sources that I use for my mounts:- Most of the internal and external battery packs supplied with mounts, assume the use of 8-off 1.5V alkaline cells. NiMH and NiCd cells give a nominal 1.2V, so 10 cells are required for 12V. I have found that a pair of 6V 2600mAh packs (borrowed from my radio-controlled model sailing yachts), give a reasonable evenings observing. I have measured the current consumption of my various mounts:- The current consumption for the AZ GTI mount is likely to be similar to that of my Celestron Cosmos 90. Geoff
  17. Hello Kartik, and welcome to Stargazers Lounge. If you Google "Dobsonian Base DIY" you should get many links and YouTube videos giving details about making a base, including those for this site (Stargazers Lounge) and its USA equivalent, "Cloudy Nights. The various articles will give you an idea of what is involved, and the level of woodworking skill required. You will also need eyepieces. The eyepiece collection can be built up as funds permit, but I would start with a 32m Plossl, and a x2 Barlow; both 1.25" diameter. Geoff
  18. Not quite, even cheaper, Screwfix's galvanised builder's strip, a few bits of double-sided sticky foam, and a couple of nuts and bolts from my "come-in-handy" bits box. Even the wood was recycled from something else. Geoff
  19. And the budget mounting option.... This is my first telescope, a Tasco 3T, 3", 700mm, and 0.963" eyepieces, bought in 1986 to see Halley's Comet; it's a fork-and-rod Az/Alt mount. This is my DIY ring and dovetail assembly and this is the setup on my Skymax mount, for full GoTo. Geoff
  20. Still very pleased with it. It has a definite advantage over my Skywatcher mounts, in that I can enter a comet's orbital parameters and do a Goto. With the Skywatcher Synscan system, I have to find the RA & Dec of the comet, for the time/date I want to observe, and then enter them in the handset. As I understand it, equipment availability in the UK is very limited due to Covid/Brexit delivery through the ports, combined with a higher demand during the lockdowns. Geoff
  21. There is a definitive guide to collimation written by Astro Baby. If you do a search, using "Astro Baby", on this site, there should be links to the document, and other excellent advice to get you going. The most important advice that I have gained from the experts on this site, is to adjust the secondary with the main tube horizontal, so that if anything falls, it will not drop onto the primary mirror. Geoff
  22. When I use my (colour) camera, I tend to use Sharpcap to display and capture images. The focus is a bit of problem, but Sharpcap includes some focus quality indication functions, and I find that my best images correspond with the highest focus quality indications. I have not tried the SS yet with the recent sunspots, but I would expect these to make a sharp focus easier than using the edge of the disk. Geoff
  23. I have the Heritage 130p and the Heritage Virtuoso with 90p MCT (at home) and 114 Newtonian (holiday home) optical tubes. Both systems are very good. When I bought the 130p, the 150p had not been manufactured, and I would probably have gone for the 150p, had it been available. This is an idea of size, including a 1 foot/30 cm ruler. These are a few additions that I have made to the 130p's mount. The green patio stool/table makes an excellent stand, as does the round glass-topped table in the background of the first photo. The Virtuoso mount has 3 modes: (1) fully manual - similar to the 130p's mount, (2) tracking - useful when changing eyepieces, (3) full GoTo with the Synscan handset borrowed from my Skyliner mount. Geoff
  24. I have the same Baader zoom. It is essentially a 1.25" eyepiece, but with the additional thread to fit a 2" sleeve. The 2" sleeve option is purely there to use the zoom with a 2" focuser, but does not give any optical improvement that I have noticed. Geoff
  25. I use my GPCAM V2, with SharpCap running on the laptop. The challenge is to get enough shade around the laptop's screen to see the fine detail, and so optimise focus, scan rate and camera gain. I have found the best way is to stretch an old bath towel from the back of the screen across to over my head. Others may have a more elegant method for viewing a laptop in bright sunlight. Geoff
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